Financial market trauma is business as usual these days. This modern era of danger began two decades ago.

I recall the beginning of a stock market slide on Oct. 19, 1987, as I conducted a morning interview with a Merrill Lynch strategist on Wall Street. Once we realized the magnitude of the drop, I spent the rest of the day hurtling around New York in a TV crew van interviewing experts and scared investors.

I remember standing in front of the New York Stock Exchange at the end of that trading day in which the Dow Jones industrial average lost 22.6 percent of its value. I wondered if we had seen the end of the financial world as we knew it.

In a way, we had. The market would gradually recover. Investors would learn to accept trauma accelerated by quick-trigger computers sending information worldwide.

Another trauma was the bursting of the dot-com bubble in which nouveau fortunes evaporated overnight. More uplifting was the NYSE opening bell when trading resumed after the 9-11 attacks.

There is modest daily trauma, as markets worry over interest rates, credit problems or China's economy.

The frequency with which financial trauma occurs can render investors emotionally immune to all but the steepest nose dives. Those garner headlines and attention, often prompting investors to sell when they shouldn't. The lesser events seem like elevator music.

The real danger is to lose sight of your investments altogether. You fail to notice gradual differences in how the various components perform, you don't make any adjustments, and you're left unprepared for surprises.

Mark Twain was right: Danger can lurk in any month for investors. While no one should panic, to hibernate through any of them the rest of this year or beyond could be an investor's downfall.